Method and apparatus for selectively classifying poultry eggs

ABSTRACT

An apparatus for classifying a plurality of poultry eggs includes means for detecting the opacities of the eggs, means for detecting the temperatures of the eggs, and means for classifying the eggs using the opacities and the temperatures of the eggs. A method for classifying poultry eggs includes measuring the opacities of the eggs, measuring the temperatures of the eggs, and classifying the eggs as a function of the opacities and the temperatures of the eggs.

RELATED APPLICATIONS

This is a continuation application of U.S. Pat. application Ser. No.09/563,218, filed May 2, 2000 now U.S. Pat. No. 6,234,320, which is acontinuation-in-part application of U.S. Pat. application Ser. No.09/309,794 filed May 11, 1999, now abandoned, the disclosures of whichare hereby incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

The present invention concerns methods and apparatus for evaluating andtreating poultry eggs, and, in particular, concerns methods andapparatus for non-invasively candling poultry eggs to determine theconditions of the eggs and to handle and treat the eggs in accordancewith such determination.

BACKGROUND OF THE INVENTION

Discrimination between poultry eggs on the basis of some observablequality is a well-known and long-used practice in the poultry industry.“Candling” is a common name for one such technique, a term which has itsroots in the original practice of inspecting an egg using the light froma candle. As is known to those familiar with poultry eggs, although eggshells appear opaque under most lighting conditions, they are in realitysomewhat translucent, and when placed in front of a direct light, thecontents of the egg can be observed.

In most practices, the purpose of inspecting eggs, particularly “tableeggs” for human consumption, is to identify and then segregate thoseeggs which have a significant quantity of blood present, such eggsthemselves sometimes being referred to as “bloods” or “blood eggs.”These eggs are less than desirable from a consumer standpoint, makingremoval of them from any given group of eggs economically desirable.

U.S. Pat. Nos. 4,955,728 and 4,914,672, both to Hebrank, describe acandling apparatus that uses infrared detectors and the infraredradiation emitted from an egg to distinguish live from infertile eggs.

U.S. Pat. No. 4,671,652 to van Asselt et al. describes a candlingapparatus in which a plurality of light sources and corresponding lightdetectors are mounted in an array, and the eggs passed on a flat betweenthe light sources and the light detectors.

In many instances it is desirable to introduce a substance, via in ovoinjection, into a living egg prior to hatch. Injections of varioussubstances into avian eggs are employed in the commercial poultryindustry to decrease post-hatch mortality rates or increase the growthrates of the hatched bird. Similarly, the injection of virus into liveeggs is utilized to propagate virus for use in vaccines. Examples ofsubstances that have been used for, or proposed for, in ovo injectioninclude vaccines, antibiotics and vitamins. Examples of in ovo treatmentsubstances and methods of in ovo injection are described in U.S. Pat.No. 4,458,630 to Sharma et al. and U.S. Pat. No. 5,028,421 toFredericksen et al., the contents of which are hereby incorporated byreference as if recited in full herein. The selection of both the siteand time of injection treatment can also impact the effectiveness of theinjected substance, as well as the mortality rate of the injected eggsor treated embryos. See, e.g., U.S. Pat. No. 4,458,630 to Sharma et al.,U.S. Pat. No. 4,681,063 to Hebrank, and U.S. Pat. No. 5,158,038 toSheeks et al. U.S. Patents cited herein are hereby incorporated byreference herein in their entireties.

In ovo injections of substances typically occur by piercing the eggshell to create a hole through the egg shell (e.g., using a punch ordrill), extending an injection needle through the hole and into theinterior of the egg (and in some cases into the avian embryo containedtherein), and injecting the treatment substance through the needle. Anexample of an injection device designed to inject through the large endof an avian egg is disclosed in U.S. Pat. No. 4,681,063 to Hebrank; thisdevice positions an egg and an injection needle in a fixed relationshipto each other, and is designed for the high-speed automated injection ofa plurality of eggs. Alternatively, U.S. Pat. No. 4,458,630 to Sharma etal. describes a bottom (small end) injection machine.

In commercial poultry production, only about 50% to 90% of commercialbroiler eggs hatch. Eggs that do not hatch include eggs that were notfertilized (which may include rots), as well as fertilized eggs thathave died (often classified into early deads, mid-deads, rots, and latedeads). Infertile eggs may comprise from about 5% up to about 25% of alleggs set. Due to the number of dead and infertile eggs encountered incommercial poultry production, the increasing use of automated methodsfor in ovo injection, and the cost of treatment substances, an automatedmethod for identifying, in a plurality of eggs, those eggs that aresuitable for injection and selectively injecting only those eggsidentified as suitable, is desirable.

U.S. Pat. No. 3,616,262 to Coady et al. discloses a conveying apparatusfor eggs that includes a candling station and an inoculation station. Atthe candling station, light is projected through the eggs and assessedby a human operator, who marks any eggs considered non-viable.Non-viable eggs are manually removed before the eggs are conveyed to theinoculating station.

SUMMARY OF THE INVENTION

According to embodiments of the present invention, a method forclassifying poultry eggs includes providing a plurality of eggs eachhaving a respective physical egg location, measuring the opacities ofthe eggs, measuring the temperatures of the eggs, and classifying theeggs as a function of the opacities and the temperatures of the eggs.The step of classifying includes identifying clear eggs of the pluralityof eggs using the opacities of the eggs, determining a spatialtemperature trend among the plurality of eggs using the identificationof the clear eggs, and identifying live eggs of the plurality of eggsusing the spatial temperature trend.

Preferably, the step of determining a spatial temperature trend includesgenerating a temperature trend map including a predicted egg temperaturefor each egg location. The step of identifying the live eggs may includecomparing the measured temperatures and the predicted temperatures.

The step of classifying may include correcting the egg temperatures forrelative egg locations using the identification of the clear eggs, andidentifying live eggs of the plurality of eggs using the corrected eggtemperatures. The step of identifying live eggs may include determininga threshold temperature, comparing the corrected egg temperatures to thethreshold temperature, and classifying the eggs having a corrected eggtemperature greater than the threshold temperature as live.

The method may include identifying upside-down eggs and excluding thetemperatures of the upside-down eggs from the temperature trenddetermination.

According to further embodiments of the present invention, a method forclassifying poultry eggs includes measuring the opacities of the eggs,measuring the temperatures of the eggs, and classifying the eggs as afunction of the opacities and the temperatures of the eggs. The step ofclassifying includes identifying clear eggs of the plurality of eggsusing the opacities of the eggs, and identifying live eggs of theplurality of eggs using the temperatures of the eggs. The step ofidentifying live eggs is facilitated by the identification of the cleareggs.

The step of classifying may include identifying a remaining group of theeggs, the remaining group not including the clear eggs, and identifyinglive eggs in the remaining group using the temperatures of the eggs ofthe remaining group and not the temperatures of the clear eggs. Themethod may further include identifying at least one other class ofnon-live eggs, preferably early dead eggs. The eggs may be physicallyseparated into at least three groups including a live egg group, a clearegg group, and a non-live and non-clear egg group.

According to other embodiments of the present invention, an apparatusfor classifying a plurality of poultry eggs each having an opacity and atemperature includes means for detecting the opacities of the eggs,means for detecting the temperatures of the eggs, and means forclassifying the eggs using the opacities and the temperatures of theeggs. The means for classifying identifies clear eggs of the pluralityof eggs using the opacities of the eggs, and identifies live eggs of theplurality of eggs using the temperatures of the eggs. The identificationof live eggs is facilitated by the identification of the clear eggs.

The means for classifying may correct the egg temperatures for relativeegg locations using the identification of the clear eggs, and identifylive eggs of the plurality of eggs using the corrected egg temperatures.The means for classifying may identify a remaining group of the eggs,the remaining group not including the clear eggs, and identify live eggsin the remaining group using the temperatures of the eggs of theremaining group and not the temperatures of the clear eggs. The meansfor classifying may identify at least one other class of non-live eggs,preferably early dead eggs. The apparatus may include an injectoroperative to inject live eggs with a treatment substance.

Preferably, the means for detecting the opacities of the eggs includes alight candling system which detects the opacities of the eggs andgenerates opacity signals corresponding to the egg opacities, the meansfor detecting the temperatures of the eggs includes a thermal candlingsystem which detects the temperatures of the eggs and generatestemperature signals corresponding to the egg temperatures, and the meansfor classifying the eggs includes a controller which receives theopacity and temperature signals and classifies the eggs as a function ofthe opacities and temperatures of the eggs, the controller beingoperative to selectively generate a control signal based on the eggclassifications. The light candling system may comprise an infraredemitter and an infrared detector, and the thermal candling system maycomprise an infrared sensor.

According to further embodiments of the present invention, a method forclassifying poultry eggs includes providing a plurality of eggs eachhaving a respective physical egg location, measuring the temperatures ofthe eggs, and classifying the eggs as a function of the temperatures ofthe eggs. The step of classifying includes determining a spatialtemperature trend among the plurality of eggs, and identifying live eggsof the plurality of eggs using the spatial temperature trend.

The step of determining a spatial temperature trend may includegenerating a temperature trend map including a predicted egg temperaturefor each egg location. The step of classifying may include correctingthe egg temperatures for relative egg locations, and identifying liveeggs of the plurality of eggs using the corrected egg temperatures.

Objects of the present invention will be appreciated by those ofordinary skill in the art from a reading of the Figures and the detaileddescription of the preferred embodiments which follow, such descriptionbeing merely illustrative of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an apparatus according to the presentinvention for selectively classifying, sorting and treating poultryeggs;

FIG. 2 is a top view of a flat of eggs in a candling station of theapparatus of FIG. 1;

FIG. 3 is a side elevational view taken along the line 3—3 of FIG. 2;

FIG. 4 is an end elevational view taken along the line 4—4 of FIG. 2;

FIG. 5 is a detailed view of a light source mounting block and a lightdetector mounting block of the apparatus of FIG. 1;

FIG. 6 is a flow chart representing a method according to the presentinvention for selectively classifying, sorting and treating poultryeggs;

FIG. 7 is a side elevational view of a treatment station forming a partof the apparatus of FIG. 1;

FIG. 8 is an enlarged view of an injection head of the treatment stationof FIG. 7;

FIG. 9 is a histogram of a distribution of measured temperatures of anexemplary array of eggs;

FIG. 10 is a histogram of the distribution of corrected temperatures ofthe array of eggs of FIG. 9, wherein the temperatures have beencorrected without using light candling data;

FIG. 11 is a histogram of the distribution of corrected temperatures ofthe array of eggs of FIG. 9, wherein the temperatures have beencorrected using light candling data; and

FIG. 12 is a flow chart representing a further method according to thepresent invention for selectively classifying, sorting and treatingpoultry eggs.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention now will be described more fully hereinafter withreference to the accompanying drawings, in which preferred embodimentsof the invention are shown. This invention may, however, be embodied inmany different forms and should not be construed as limited to theembodiments set forth herein; rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. Likenumbers refer to like elements throughout.

The present invention may be carried out with any types of avian eggs,including chicken, turkey, duck, geese, quail, and pheasant eggs.Chicken eggs are particularly preferred.

Typically, eggs are inoculated on or about the eighteenth day of age. Atsuch time, an egg may be one of several commonly recognized types. Theegg may be a “live” egg, meaning that it has a viable embryo. The eggmay be a “clear” or “infertile” egg, meaning that it does not have anembryo. More particularly, a “clear” egg is an infertile egg that hasnot rotted. The egg may be an “early dead” egg, meaning that it has anembryo which died at about one to five days old. The egg may be a“mid-dead” egg, meaning that it has an embryo which died at about fiveto fifteen days old. The egg may be a “late mid-dead” egg, meaning thatit has an embryo which died at about fifteen to eighteen days old. Theegg may be a “rot” egg, meaning that the egg includes a rotted infertileyolk (for example, as a result of a crack in the egg's shell) or,alternatively, a rotted, dead embryo. While an “early dead”, “mid-dead”or “late mid-dead egg” may be a rotted egg, those terms as used hereinrefer to such eggs which have not rotted. The egg may be an “empty” egg,meaning that a substantial portion of the egg contents are missing, forexample, where the egg shell has cracked and the egg material has leakedfrom the egg. Additionally, from the perspective of many egg detectingand identifying devices, an egg tray may be missing an egg at aparticular location, in which case, this location may be termed a“missing” egg. An egg may be placed in an egg tray such that it is an“upside-down” egg, meaning that the egg has been placed in the tray suchthat the air cell thereof is mislocated, typically with the blunt enddown. Clear, early-dead, mid-dead, late mid-dead, and rot eggs may alsobe categorized as “non-live” eggs because they do not include a livingembryo.

Typically, eggs are held in trays on racks in carts for incubation inrelatively large incubators. At a selected time, typically on theeighteenth day of age, a cart of eggs is removed from the incubator forthe purposes of, ideally, separating out unfit eggs (namely, deads,rots, empties, and clears), inoculating the live eggs and transferringthe eggs from the setting flats to the hatching baskets. Certainpractical aspects of the incubation, handling and measuring processesmay substantially diminish the accuracy of the methods and apparatus fordistinguishing between live and dead eggs using thermal candlingdevices. The temperatures of the eggs may differ based on their relativelocations in the incubator because different temperatures or air flowsmay be present at different locations in the incubator. Also, thethermal environment outside of the incubator may be poorly controlled.As a result, different trays and sections of trays often experiencedifferent cooling rates depending on their positions in the cart andexposure to air drafts.

In the candling method and apparatus described in U.S. Pat. No.4,914,672 to Hebrank, for example, a thermal candling system measuresthe temperature of each egg from the bottom. The thermal candling systemdetermines a threshold temperature. Eggs above the threshold temperatureare deemed live and eggs below the threshold temperature are deemednon-live (which includes dead and clear eggs).

The accuracy of the chosen threshold temperature is jeopardized bynon-uniform cooling conditions as discussed above. In order to minimizethe risk of improperly identifying a live egg as a non-live egg, thethreshold temperature is generally set lower than the predictedtemperature of a live egg. Correction factors have been applied tobetter approximate the appropriate threshold temperatures for differenteggs or groups of eggs; however, these correction factors are not asaccurate as desired.

While it is disadvantageous to discard live eggs, it is alsodisadvantageous to retain certain non-live eggs. In particular, if rotor dead eggs are retained and inoculated, the inoculating needle may becontaminated, risking infection of subsequent live, healthy eggs.Furthermore, the treatment substance is wasted if injected in a non-liveegg.

Furthermore, in some instances, it may be desirable to identify cleareggs (i.e., infertile, non-rotted eggs) and early dead eggs. While notsuitable for producing broilers, these eggs may be useful for commercialfood service or low grade food stock (e.g., dog food). The presence ofbacterial contamination from rots decreases the value of this foodstock.

The present invention is directed to a method and an apparatus foridentifying types of eggs which use both a thermal candling system and alight candling system. The light candling system augments the accuracyof the thermal candling system and may identify types of eggs which thethermal candling system may not effectively identify. By use of theinventive method and apparatus, the number of improperly discarded liveeggs and the number of inoculated rotted or dead eggs may each bereduced. Additionally, clear and/or early dead eggs may be positivelyidentified and separated from other types of eggs.

According to preferred embodiments, the light candling system is used toidentify clear eggs. The thermal candling system is used to distinguishlive eggs from non-live eggs using a threshold temperature. Thethreshold temperature is preferably determined by measuring thetemperatures of all or selected ones of the eggs in a tray and derivingtherefrom the temperature above which the eggs are expected to be live.The accuracy of this determination is facilitated by use of datacollected from the light candling system. In this way, theidentification of live eggs versus non-live eggs (i.e., dead, rotted,empty, missing and clear eggs) may be more accurately made, therebyreducing the number of improperly retained rotted or dead eggs whichmight otherwise contaminate inoculation needles, and minimize thepossibility of discarding a live egg.

To further enhance classification accuracy, a spatial temperature trendamong the eggs may be determined to account for temperature variationsacross the flat due to non-uniform micro-environments (for example,resulting from non-uniform air flows in incubators and hallways).Preferably, a temperature trend map for the eggs is generated and usedto evaluate the measured egg temperatures. The determination of thethreshold temperature may be facilitated by correcting or compensatingthe measured egg temperatures. Preferably, the amount of correction isdetermined, at least in part, by considering the temperatures of alleggs except the non-live eggs which have been identified by the lightcandling system as clear eggs.

According to further preferred embodiments, the eggs are classified bycomparing the measured temperatures thereof to corresponding predictedtemperatures of a temperature trend map. Preferably, the predictedtemperatures are determined, at least in part, by adjusting or excludingthe temperatures of the eggs which have been identified as clear eggs bythe light candling system.

The determination of a spatial temperature trend may also be used inclassifying the eggs without using the light candling data andidentification of clears to determine the amount of correction or thepredicted temperatures or to otherwise facilitate the classification.Either of the foregoing methods may be modified in this manner.

The eggs which are classified as live may be treated by inoculation witha treatment substance or the like. Because the light candling systemidentifies clear eggs and early dead eggs, these eggs may be separatedfrom the other non-live eggs for other uses. That is, the non-live eggsmay be further classified as clear or early dead and non-clear or earlydead. In this way, the light candling system supplements the thermalcandling system which may not reliably distinguish between clear orearly dead eggs and other non-live eggs. Optionally, the non-live eggsmay be further classified as infertiles and early dead or various stagesof mid-dead. The classified eggs are then physically separated andtransported such that the live eggs are passed on for inoculation orother treatment, the clear eggs (and, optionally, the early dead eggs)are diverted for collection for other uses, and the remaining non-liveeggs are discarded.

In the case of upside-down eggs, the light candling system may be usedto determine if the egg is clear as opposed to live or dead. Optionally,the thermal candling system may include sensors for measuring thetemperatures at each end of an upside-down egg to determine whether theegg is live or non-live.

The light candling system may be used to further estimate the quantitiesor statistics of early mid-dead, mid-dead, late mid-dead, rot and emptyeggs. Such information may be desired for the purposes of evaluatinggroups of eggs.

Turning to the preferred embodiments of the method and the apparatus ingreater detail, said method and apparatus identify, classify, report,sort, and inoculate or otherwise treat eggs of a group of eggs. It willbe appreciated that various aspects and features of the method andapparatus may be omitted or used separately from the described methodand apparatus. The method and apparatus employ both a thermal candlingsystem and a light candling system to identify each or selected ones ofthe eggs. A controller of the apparatus collects data regarding the eggsfrom the thermal candling system and the light candling system,classifies the eggs, and sorts or treats the eggs in accordance withtheir classifications and pre-determined standards or parameters.

With reference to FIG. 1, an apparatus 10 according to the presentinvention is shown schematically therein. The apparatus 10 is used tosort and treat a plurality of eggs 2 which are preferably provided in aflat 12. The apparatus 10 includes an identification or candling station8 (hereinafter, “the candling station 8”). The candling station 8 inturn includes a light candling system 20 and a thermal candling system30. The light candling system 20 and the thermal candling system 30 eachserve to assess various characteristics of the eggs which may be used toevaluate and classify the eggs.

The light candling system 20 and the thermal candling system 30 areoperatively connected to a controller 40. The controller 40 controls thecandling station 8 and receives and processes signals from the candlingstation 8. The controller 40 also collects and analyzes data regardingeach or selected ones of the eggs from the candling station 8 and, usingthis data, classifies the eggs as to type. A display 42 and a usercontrolled interface 44 are provided to allow the operator to interactwith the controller 40.

A sorting station 60 may be provided downstream of the candling station8. As discussed below, the controller 40 generates a selective removalsignal based on the presence and relative position of each suitable eggto cause the sorting station 60 to remove prescribed classes of eggs.The prescribed classes preferably include clear eggs and may alsoinclude other non-live eggs.

A treatment station 50 is provided downstream of the candling system 8.As discussed below, the controller 40 generates a selective treatmentsignal based on the presence and relative position of each suitable eggto cause the treatment station 50 to treat, for example, by inoculationwith a treatment substance, prescribed classes of eggs.

A conveying system 7 serves to transport the eggs through and,optionally, between, each of the stations 8, 50, and 60. The conveyingsystem 7 includes conveyors 7A, 7B and 7C associated with the stations8, 60 and 50, respectively. The conveyors 7A, 7B, 7C may be separateconveyors or a continuously configured conveyor.

With reference to FIGS. 2-5, the candling station 8 and the associatedconveyor 7A are shown therein. As discussed above, the candling system 8includes the light candling system 20 and the thermal candling system30. The conveyor 7A transports the flat 12 of eggs 2 by each of thelight candling system 20 and the thermal candling system 30.

The light candling system 20 is preferably a light candling system asdescribed in U.S. Pat. No. 5,745,228 to Hebrank et al., which is herebyincorporated herein by reference in its entirety, wherein light ispulsed at a frequency different from (and preferably higher than)ambient light. Suitable light candling systems include the lightcandling system forming a part of the Vaccine Saver™ vaccine deliverysystem available from Embrex, Inc. of Research Triangle Park, N.C. withsuitable modifications. In overview, the light candling system of U.S.Pat. No. 5,745,228 comprises a photodetector associated with aphotodetector amplifier and filter circuit, which is in turn associatedwith a PC analog input board, and a photoemitter (an infrared emitter)associated with an IR emitter driver circuit, in turn associated with adigital output board. The photoemitter and photodetector are positionedto be on opposite sides of an egg, preferably with the photodetectorabove and the photoemitter below the egg, but these positions are notcritical and could be reversed, or the emitter and detector placed in adifferent orientation, so long as light from the emitter illuminates theegg to the detector. The input and output boards may be installed in apersonal computer, with operation of the system monitored on the displayscreen of the PC computer.

In operation, the light candling system 20 uses time to allow accuratemeasurement of the light from a single egg. Light is generated in shortbursts from each photoemitter (e.g., 50 to 300 microseconds) and thecorresponding photodetector only monitors while its correspondingphotoemitter is operational. To reduce the effect of ambient light, theoutput of a photodetector when no light is on is subtracted from thereading when the light is on. Preferably, light is generated in a shortburst from a photoemitter, and the corresponding photodetector monitorsthe light level immediately before, during, and immediately after theburst of light is generated. A flat of eggs is continuously “scanned” asit moves through the identifier with each detector-source pair activeonly while at least adjacent, and preferably all other, pairs arequiescent.

Turning to the construction of the light candling system 20 in moredetail and with reference to FIGS. 2-5, the light candling system 20includes an infrared light emitter mounting block 11 and an infraredlight detector mounting block 21 mounted on the conveyor 7A. Theinfrared light emitter mounting block 11 is comprised of an opaque blackplate 16 with the infrared emitters 17 (Photonics Detectors, Inc. Partnumber PDI-E805) mounted thereto. These emitters include an integrallens, but a nonintegral lens system could also be provided for theemitter. These gallium-arsenide light-emitting diodes emit infraredlight with a wavelength of 880 nanometers and can be switched on or offwith activation times of about one microsecond. An opaque polymer block18 that is 0.5 inches thick has ¼ inch diameter holes 18A boredtherethrough in corresponding relation to each emitter. A 0.040″polycarbonate sheet 19 (opaque except for a 0.25 inch circle above eachemitter) overlies the block 18. The structure of the mounting block thusprovides an optical aperture positioned between the egg and the lightemitters 17. In one embodiment, sheets available commercially foroverhead projector transparencies are used.

Likewise, the infrared light detector mounting block 21 is comprised ofan opaque back plate 26 with the infrared detectors 27 (TexasInstruments Part number TSL261) mounted thereto. Integral lenses ornon-integral lens systems could optionally be provided with thedetectors. An opaque polymer block 28 that is 0.5 inches thick has ¾inch diameter holes 28A bored therethrough in corresponding relation toeach emitter. A 0.040 inch polycarbonate sheet 29 (opaque except for a0.25 inch circle above each detector) overlies the block 28. Thepolycarbonate sheets may be a light-blocking, infrared transmissivepolymer that have about 90% transmittance of wavelengths between 750 and2000 nanometers. The infrared light from the emitters has a wavelengthnear 880 nanometers. Thus, the sheets serve, at least in part, to blockand filter ambient light. Again, the structure of the mounting blockthus provides an optical aperture positioned between the egg and thelight detectors 27.

In all cases, opaque materials are preferably black. The apparatus isconfigured so that the distance “a” from the top of the egg to thepolymer film 29 is from ½ to one inch, and so that the distance “b” fromthe bottom of the egg to the polymer film 19 is from ½ to one inch, witha distance of 0.5 inches preferred. Note that some egg flats and thevariety of egg sizes cause this distance to typically range from ⅜ inchto one inch. The size of the viewed area on the egg is typically fromabout 0.1 inches to about 0.3 inches in diameter. Smaller areastypically give better rejection of light reflected off of adjacent eggs.

A switching circuit is operatively associated with the light source forcycling the intensity of the light from the emitters 17 at a frequencygreater than 100 cycles per second, and preferably at a frequencygreater than 200 or 400 cycles per second. An electronic filter isoperatively associated with the light detectors 27 and is configured todistinguish light emitted from the light source from ambient light(i.e., by filtering out higher and/or lower frequency light signalsdetected by the detector). All may be conventional circuitry, andnumerous variations thereon will be readily apparent to those skilled inthe art.

In operation, each emitter 17 is typically turned on for about 250microseconds. The output of each photodetector 27 is amplified by abandwidth-limited filter (2 kHz low pass filter combined with a 1.0 kHzhigh pass filter). The filter maximizes detection of the 250 microsecondpulses of light from the photoemitters while minimizing noise fromeither electronic circuitry or stray light in the environment. Theoutput from each filter is sampled about 120 microseconds after thecorresponding emitter is turned on. The samples are digitized andrecorded by the computer. A second sample is taken about 250microseconds after the corresponding emitter is turned off. Theoff-light sample when subtracted from the on-light sample furtherimproves rejection of ambient lighting around the identifier.

In another embodiment of the light emitter mounting block 11, the diodesare mounted in an opaque polymer block 18 that positions the diodes andprotects them from water and dust in the working environment. A flatsapphire window above each diode is transparent to the light from thediode. Similarly, the light detector mounting block 21 may be comprisedof an opaque back plate 26 with lensed infrared detectors (IPL Partnumber IPL10530DAL) mounted thereto. An opaque polymer block 28 that is0.6 inches thick has 0.33 inch diameter holes bored therethrough incorresponding relation to each emitter. A transparent sapphire windowallows light passing through an egg to illuminate the detector above it.Some of the photoemitters may be slightly off set from the center lineof the eggs so that they miss the conveyor belts.

In another embodiment, in the operation of an apparatus as describedabove, each emitter is typically turned on for about 70 microseconds.The output from each detector is sampled just before and about 70microseconds after the corresponding emitter is turned on. A thirdsample is taken about 70 microseconds after the corresponding emitter isturned off. The samples are digitized and recorded by the computer. Theoff-light samples are averaged and subtracted from the on-light sampleto improve rejection of ambient lighting around the identifier.

While preferred light candling systems have been described, any othersuitable device for measuring the opacities of eggs may be used in themethod and apparatus of the present invention. Such other suitabledevices will be apparent to those of skilled in the art from uponreading the description herein.

The controller 40 is operatively connected to and actuates the infraredemitters 17 to pulse light at a frequency different than (and preferablyhigher than) the ambient light as described above. A portion of thelight from the emitters 17 is transmitted through the eggs 2 andreceived by the corresponding detectors 27. The controller 40 isoperatively connected to and receives signals generated by each detector27 corresponding to the light level (or irradiance) of the glowing eggand the resulting intensity of the light incident at the detector 27. Inthis manner, the controller is provided by the light candling system 20with assessments of the respective opacities of the eggs. It is notnecessary that the detectors 27 be collinearly aligned with theirassociated emitters 17 because the light entering the eggs is diffusedby the shells and contents of the eggs.

The thermal candling system 30 is preferably a thermal candling systemas described in U.S. Pat. No. 4,914,672 and in U.S. Pat. No. 4,955,728,each to Hebrank, each of which are hereby incorporated herein in theirentireties. The thermal candling system 30 includes a mounting bracket31 and a plurality of infrared thermal sensors 37 mounted therein atlocations corresponding to each egg 2 in a row of the flat 12. Thethermal sensors 37 are operative to measure the infrared radiationemitted by each egg passed thereby. The controller 40 is operativelyconnected to each of the infrared thermal sensors 37 to receive signalsfrom the sensor 37 corresponding to the temperature at the sensor 37.Means associated with either the sensors 37 or the controller 40 convertthe infrared radiation measurement to a corresponding temperature value,typically using a standard algorithm and calibration data. The sensors37 may be infrared thermometers which produce an output signal indegrees Celsius or Fahrenheit and require no further conversion. As analternative, the temperature measurements may be made by contacttemperature sensors (not shown) such as thermistors or thermocoupleswhich are placed against sides or non-air cell ends of the eggs or by aninfrared video camera.

As used herein, the designation “infrared radiation” refers toelectromagnetic radiation having a wavelength of between about 2.5 andabout 50 microns (or expressed differently, that having a frequency ofbetween about 200 and about 4000 inverse centimeters cm⁻¹ or “wavenumbers”). As understood by those familiar with infrared (IR) radiationand the IR spectrum, the frequencies of electromagnetic radiationgenerally characterized as infrared are emitted or absorbed by vibratingmolecules, and such vibrations generally correspond to the thermal stateof a material in relation to its surroundings. All solid bodies whosetemperatures are above absolute zero radiate some infrared energy, andfor temperatures up to about 3500 K (3227° Celsius, 5840° Fahrenheit),such thermal radiation falls predominately within the infrared portionof the electromagnetic spectrum. There thus exists a ratherstraightforward relationship between the temperature of a body and theinfrared radiation which it emits. In the present invention, themonitoring of radiation in the range of 8-14 microns is currentlypreferred.

As further understood by those familiar with electromagnetic radiation,however, wavelengths below 2.5 microns (usually 0.8 to 2.5 microns or4000-12,500 cm⁻¹) are also considered as the “near IR” portion of theelectromagnetic spectrum, and represent vibrational “overtones” and lowlevel electronic transitions. Similarly, wavelengths above 50 microns(usually 50 to about 1000 microns or 10-200 cm⁻¹) are considered to be“far IR” portion of the electromagnetic spectrum and represent energyassociated with molecular rotations.

It will thus be understood that the designation “infrared” is used in adescriptive rather than a limiting sense and that measurement of thermalradiation from eggs which falls outside of these particular frequenciesis encompassed by the scope of the present invention.

Optionally, the thermal candling system 30 may include thermal sensors37 positioned to detect the temperature at both ends of each egg. Inthis manner, an accurate reading of the temperatures of eggs positionedupside-down in the flat may be made. The controller 40 should beprogrammed to recognize the presence of an upside-down egg from thetemperature differential between the associated, opposed thermal sensors37, and to classify the egg according to the temperature measured at thenon-air cell end. Further, the controller 40 may be operative to reportthe presence and location of the upside-down egg via the display 44.

Preferably, the eggs are carried in egg flats 12 as described herein;however, as will be apparent to those ordinarily skilled in the art, anymeans of presenting a plurality of eggs over time to the candlingstation 8 for identification of suitable eggs can be used in the presentmethods. The eggs may pass one at a time under the candling station 8or, as described herein, the candling station 8 may be configured sothat a number of eggs can pass under the candling station 8simultaneously.

Any flat of eggs with rows of eggs therein may be used, and while fiverows are illustrated in the flat 12 shown schematically in FIG. 2, theflat may contain any number of rows, such as seven rows of eggs, withrows of six and seven being most common. Eggs in adjacent rows may beparallel to one another, as in a “rectangular” flat, or may be in astaggered relationship, as in an “offset” flat (not shown). Examples ofsuitable commercial flats include, but are not limited to, the“CHICKMASTER 54” flat, the “JAMESWAY 42” flat and the “JAMESWAY 84” flat(in each case, the number indicates the number of eggs carried by theflat). As illustrated in FIGS. 2 and 3, the flat 12 is an open bottomsetting flat and carries twenty-five eggs in a fixed array of five rowsof five eggs each.

The flat 12 rides on the conveyor 7A. As shown, the conveyor 7A includesdrive chains 13, chain drive motor 14 and chain drive dogs 15 that movethe flat along the guide rails 22 adjacent the path of the chain 13. Inan alternate, preferred embodiment, the chain drive and dogs arereplaced with a pair of polymeric conveyor belts riding on supportrails, which conveyor belts are ⅜ inch diameter and ride on 0.5 inchframes. Such belts are as found on egg injection equipment, particularlythe EMBREX INOVOJECT® egg injection apparatus, and are desirable fortheir comparability with operator safety and corrosion resistance. Eggflats are typically moved at rates of 10 to 20 inches per second. Theeggs are preferably placed in the flat such that the air cell endsthereof do not pass adjacent the thermal sensors 37.

As discussed above, the infrared emitters 17, the infrared detectors 27and the infrared thermal sensors 37 are each operatively connected tothe controller 40. The controller 40 includes processing means which: 1)generate control signals to actuate and deactuate the emitters 17; 2)receive and process the signals from the detectors 27 and the sensors37; 3) process and store data associated with each egg; and 4) generatecontrol signals to operate the treatment station 50 and the sortingstation 60. The controller 40 preferably includes a PC having amicroprocessor or other suitable programmable or non-programmablecircuitry including suitable software. The controller 40 may alsoinclude such other devices as appropriate to drive the emitters 17 andreceive, process or otherwise assess and evaluate signals from thedetectors 27 and the sensors 37. Suitable devices, circuitry andsoftware will be readily apparent to those of ordinary skill in the artupon reading the foregoing and following descriptions and thedisclosures of U.S. Pat. Nos. 5,745,228 to Hebrank et al. and U.S. Pat.No. 4,955,728 to Hebrank. The processing computer and other devices maybe housed in a common cabinet or separate cabinets.

The operator interface 44 may be any suitable user interface device andpreferably includes a touch screen or keyboard. The operator interface44 may allow the user to retrieve various information from thecontroller 40, to set various parameters and/or to program/reprogram thecontroller 40. The operator interface 44 may include other peripheraldevices, for example, a printer and a connection to a computer network.

With reference to FIG. 6, the eggs may be assessed, classified, sorted,treated and reported using the above described apparatus and thefollowing method. The method is premised on the discovery thatregardless of thermal surroundings, non-live eggs, and in particular,clear eggs, tend to be cooler than live eggs under those sameconditions. Because thermal surroundings and thermal history affect theabsolute temperatures of both live and non-live eggs, measurement of oneegg's individual temperature or cooling rate, standing alone, may notprovide sufficient information to determine whether the egg is live ornon-live.

The individual egg temperatures are monitored and used to determine athreshold egg temperature for the selected group of eggs, it beingunderstood that, as used herein, the term “threshold” means thecomputation of a relative standard temperature for the group againstwhich the temperatures of the individual eggs can be compared, and whichprovides a threshold for determining whether any given egg is live ornon-live. The threshold temperature is determined, at least in part, byevaluating the temperatures of those eggs identified as clear eggs.

Once the threshold temperature has been determined, the next step in themethod of the invention is the determination of the difference betweeneach individual egg temperature and the threshold temperature of theselected group, following which the resulting status of each egg may bedetermined. The classified eggs may thereafter be reported, sorted andtreated as appropriate.

Turning to the method in more detail, initially, certain parameters orthresholds are set (Block 602). These parameters may set the desiredmargins for error reflective of the determined or expected costs ofmis-classifying live eggs, clear eggs or rot eggs. The desiredthresholds for the light intensities incident at the detectors 27,including any variances, are set. Some or all of the thresholds may beset by the operator or may be fixed or preset thresholds. Some or all ofthe thresholds may also be operator set but automatically modified bythe controller 40 based on other conditions such as measured ambientlight, average light levels for clears, or average light levels forlives. The light intensities incident at the detector 27 will beinversely proportional to the opacities of the respective eggs 2. Thatis, more opaque eggs will transmit less of the light from the associatedemitters 17, thereby reducing the intensity of the light at theassociated detectors 27 corresponding amounts. The thresholds preferablyinclude threshold values L_(e), L_(c), L_(md) and L_(f), which arerelated as follows:

where:

(1) above the L_(e), the egg slot will be considered empty;

(2) between L_(e) and L_(c), the egg will be considered empty;

(3) between L_(c) and L_(md), the egg will be considered clear or earlydead;

(4) between L_(md) and L_(f), the egg will be considered mid-dead; and

(5) below L_(f), the egg will be considered fertile or rotted, but notclear, early dead or mid-dead.

Additional thresholds may be used as well. For example, thresholds maybe set which distinguish between clear and early dead or early mid-deadand late mid-dead. Also, one or more thresholds may be omitted. Forexample, the L_(md) threshold may serve as the L_(f) threshold such thatan egg for which the light intensity at the associated detector 27 isless than L_(md) will be considered mid-dead, live, rot or late dead,and intensities greater than L_(md) but less than L_(c) will beconsidered clears and early deads.

Certain temperature related values may also be set (Block 604). Forexample, standard deviations for egg temperatures may be set by anoperator or may be fixed or preset. The threshold temperatures may alsobe automatically modified by the controller 40 based on other conditionssuch as coefficient of variation of the clear eggs or the live eggs. Thecontroller may be provided with a program including an algorithm and/orlook up table for determining the threshold temperatures from themeasured live and clear egg temperatures.

The flat 12 of eggs 2 is placed on the conveyor 7A which transports theflat to the light candling system 20. Preferably, the front edge of anegg flat 12 is located either by the flat 12 moving up to a fixed stop(not shown) or by a photo-optic device (not shown), also operativelyassociated with the computer, locating the front edge of the flat.Normally the rows of emitters 17 and detectors 27 are aligned with thefront row of the flat 12 at that time. The flat 12 is then moved forwardby the conveyor system 7A while the row of detectors 27 continuouslyscan the eggs. Software associated with the controller 40 defines thepassage of rows of eggs 2 by the strong light that passes between theeggs 2 as the margin between rows moves past the detectors. As a checkon the location of rows, the computer may also monitor the running orstopped state of the conveyor motor.

Row by row, the conveyor 7A passes the eggs by the emitters 17 anddetectors 27, and the light candling system 20 measures the opacity ofeach egg or selected eggs and generates corresponding signals to thecontroller 40 (Block 606). The controller 40 processes, indexes andstores this data for each assessed egg thereby generating an opacity orlight candling data set.

The flat of eggs is also transported by the conveyor 7A through thethermal candling system 30, before, after (as shown), or simultaneouslywith the light candling step. The thermal candling system 30 measuresthe temperature (or the corresponding infrared radiation) of each eggand generates corresponding signals to the controller 40 (Block 608).The controller 40 processes, indexes and stores this data for each egg,thereby generating a temperature or thermal candling data set. Rowdetection data from the light identifier may be used to index theconveyor or signal when an egg's position is over the thermal sensor forimproved accuracy of the thermal candler.

It will be appreciated that, following the steps of assessing theopacity of each or certain eggs (by light candling) and assessing thetemperature of each egg (by thermal candling), the controller 40 willhave a temperature profile for each assessed egg and an opacity profilefor all or certain eggs. The controller 40 evaluates each egg profile bycomparing the data to the preset threshold values. According to apreferred method, the controller 40 first evaluates the eggs using thelight candling data and then evaluates the eggs using the thermalcandling data in view of the light candling data.

More particularly, the controller 40 compares the light candling datafor each assessed egg to the threshold light intensities L_(e), L_(c),L_(md), and L_(f) and classifies the eggs in accordance therewith (Block610). If, for a given egg, the light intensity exceeds L_(e), the egg isclassified as an empty slot in the flat 12 (i.e., missing). If the lightintensity is between L_(e) and L_(c), the egg is classified as an emptyegg. If the light intensity is between L_(c) and L_(md), the egg isclassified as a clear/early dead egg. If the light intensity is betweenL_(md) and L_(f), the egg is classified as a mid-dead egg. Additionally,the preferred light candling system as described above allows resolutionof the age of the mid-dead eggs by the shape and intensity of theone-dimensional image of egg transparency. If the light intensity isless than L_(f), the egg is classified as fertile or rotted, but notclear, early dead or mid-dead.

The controller 40 then uses the classifications of the eggs from thelight candling data to determine the appropriate threshold temperature(Block 616) and, optionally, to correct or compensate the temperaturevalues as measured by the thermal candling system 30 (Block 614). Asdiscussed hereinafter, this may be accomplished by different methods.

According to a preferred method (“Method A”), temperatures of all eggsclassified by the light candling system as clear, early dead or mid-deadare used to calculate an “average non-live temperature” (ANLT) byarithmetic averaging of the temperatures in this group. Any egg morethan a prescribed amount (e.g., 5° F.) cooler than the ANLT isconsidered to be upside-down (Block 612). If a second set of thermaldetectors is provided, the differentials between the temperature valuesat either end of each egg may be used to identify and classifyupside-down eggs (Block 612). If there are few or no non-live eggs on aflat, then upside-down eggs are identified as more than a prescribedtemperature amount, for example, seven degrees, cooler than the averageof all non-clear, non-mid-dead eggs on a flat. Alternatively,upside-down eggs may be identified as those eggs having a measuredtemperature more than a prescribed temperature amount, for example, fivedegrees, cooler than the warmest measured egg temperature.

The remaining eggs (i.e., those eggs not classified as clear, earlydead, mid-dead or upside-down) that are warmer than the ANLT are used tocalculate an “average live temperature” (ALT) and a “live egg standarddeviation” (LESD) by calculating the average and standard deviation ofthe measured temperature of these eggs. The “threshold temperature” (TT)that is used to distinguish live from non-live eggs is preferablytypically set halfway between the ANLT and the ALT. However, if the LESDis larger than a predetermined value, then the threshold temperature(TT) should be set to a value closer to the ANLT to lessen thepossibility that a live egg is discarded. If a flat has very few or noclear or mid-dead eggs, then the threshold temperature is set bysubtracting a temperature increment from the ALT. This increment is apreset value or based upon data from previous flats. The thresholdtemperature (TT) is calculated according to the formula:

TT=k*(ALT−ANLT)+ANLT,

where k is preferably set between 0.1 and 0.5. For LESD's at or belowthe predetermined value, k is preferably set at 0.5. For LESD's greaterthan the predetermined value, k should be reduced. The operator canenter values of k or k can be automatically set from a lookup table thatgives k as a function of LESD. The predetermined LESD value may be setby the operator or may be automatically set.

Preferably, the egg temperatures are corrected or compensated forposition of the egg in the flat to improve classification accuracy(Block 614). For example, in a hatchery hallway with cool, moving air,eggs on an outside row of a flat will cool more quickly and be coolerthan eggs located near the center of the flat. The individual eggtemperatures are corrected, preferably in the manner described below, todetermine corrected egg temperatures. The corrected or compensated eggtemperatures are used in place of the measured egg temperatures tocalculate the ALT, the ANLT and the threshold temperature (TT). Thecorrected egg temperatures are also used in place of the measured eggtemperatures for comparing to the threshold temperature to distinguishlive from non-live eggs. In order that the upside-down eggs may beidentified to remove them from the correction procedure, an ANLT ispreferably calculated using the measured, uncorrected temperatures; andthe uncorrected temperatures are compared to this ANLT to identify theupside-down eggs.

According to some preferred embodiments, the temperature correction isperformed using only those eggs that have not been determined by thelight candling to be clears. More preferably, the upside-down eggs areexcluded as well. Most preferably, the temperature correction orcompensation is performed using only “probable lives and rots” (PLR),that is, those eggs that light candling has determined are not clear,early dead, empty or mid-dead, and that thermal candling (using themeasured, uncorrected temperatures) has determined are not upside-down.

Temperature correction or compensation is accomplished by establishingthe temperature trend across the flat of eggs among the selected eggs(e.g., the non-clears or PLR's) caused by variations in the thermalenvironment, and then normalizing all of the eggs for this trend(hereinafter “predicted temperatures”). These predicted temperaturesform a Temperature Trend Map (TTM). The predicted temperatures may beexpressed by the two-dimensional, second-order, least squares fitequation:

T _(Predicted)(i,j)=(c1*i ²)+(c2*i)+(c3*j ²)+(c4*j)+c5

where:

T_(Predicted)(i,j) is the predicted temperature for an egg located atposition i and j, for example, in a row i and an intersecting column j;and

c1 to c5 are constants calculated by minimizing the sum of the squaresof the differences between the predicted and measured temperatures foreach selected egg.

After calculating the predicted temperature, the “corrected (orcompensated) temperature” for each egg is calculated by subtracting fromthe measured temperature of the egg the amount the predicted temperaturefor the egg exceeds the average flat temperature. That is:

T _(Corrected)(i,j)=T _(Measured)(i,j)−[T _(Predicted) (i,j)−T_(Average for the flat)]

where T_(average for the flat) is the simple average of the temperaturesof all eggs used in the calculation of the predicted temperatureequation.

Temperature corrections or compensations for non-uniform thermalenvironments are typically more accurate if the difference intemperatures between live and non-live eggs is not allowed to affect thecorrection. Typically, 70% to 90% of the eggs on a flat are live, 5% to25% are clears and early deads, and less than 5% are malpositions (e.g.,upside-down), mid-deads and rots. By eliminating malpositioned, clearand early dead eggs from the calculation of the predicted temperature,most of the live/dead temperature variation is removed from thepredicted temperature. In other words, by eliminating most of thenon-live eggs from the calculations, the predicted temperatures are moreaccurate and less influenced by groupings of non-live eggs which mayskew the predicted temperatures in an area of the flat. The individualcorrected egg temperatures for all of the eggs (live and non-live) areused in place of the measured egg temperatures to calculate the averagelive temperature (ALT) and the average non-live temperature (ANLT) inthe manner described above. Accordingly, the calculated thresholdtemperature (TT) reflects the correction procedure applied to all of theeggs of the flat.

After correcting or compensating the egg temperatures according tolocation, a threshold temperature can be calculated and classificationsof the eggs as live versus non-live may be made by comparing theindividual corrected egg temperatures to the threshold temperature(Block 618). Eggs having temperatures equal to or exceeding thethreshold temperature are classified as live, all other eggs areclassified as non-live. The LESD may be referenced to affirm that thecorrection of the egg temperatures was accurate.

Alternatively, and with reference to FIG. 12, the eggs may be classifiedby the following procedure (“Method B”), which also includesestablishing a spatial temperature trend among the eggs on the flat.Blocks 702-724 correspond to Blocks 602-624 except that the steps ofBlocks 614, 616 and 618 are replaced by the steps of Blocks 715, 717 and719. A measured temperature (T_(Measured) (i,j)) is obtained for eachegg by thermal candling. The clear eggs are identified using the lightcandling data and the upside-down eggs are identified using the thermalcandling data in the manners described above. The light candling datamay also be used to identify early dead, empty and/or mid-dead-eggs. Ifearly dead and/or mid-dead eggs are identified by light candling withsufficient confidence, they will be treated in the same manner as cleareggs for the remainder of the procedure and the use of the term “cleareggs” should be understood to include such eggs.

The controller generates an Adjusted Temperature Data Set (ATDS) (Block715) comprising an adjusted temperature (T_(adj) (i,j)) for each eggthat is not upside-down or empty, and wherein:

1. For eggs identified as clear eggs (and, if identified, early dead andmid-dead eggs):

T _(adj)(i,j)=T _(Measured)(i,j)+X degrees

X may be a constant or a calculated value. If X is a constant, it ispreferably about 2° F. X degrees represents the expected temperaturedifference between a live egg and a clear egg under the same conditions(i.e., in the same micro-environment).

2. The temperatures of empty and upside-down eggs are excluded as ifthey were empty slots in the flat (i.e., missing eggs).

3. For the remaining eggs:

T _(adj)(i,j)=T _(Measured)(i,j)

If any early dead and/or mid-dead eggs are not identified as such usingthe light candling data, they will be included in the remaining eggs setby default.

Thereafter, a Temperature Trend Map (TTM) is generated for the flatusing the ATDS. Preferably, the TTM may be expressed as an equation orequation set for which a predicted temperature (T_(Predicted) (i,j)) maybe determined for each egg location (i,j) (Block 717). More preferably,the TTM is generated using a two-dimensional, second order, leastsquares fit such that:

T _(Predicted)(i,j)=(c1*i ²)+(c2*i)+(c ³ +j ²)+(c4*j)+c5

where:

c1 to c5 are constants calculated by minimizing the sum of the squaresof the differences between the predicted and adjusted temperatures foreach selected egg.

T_(Predicted)(i,j) represents the expected temperature of an egg locatedat position i and j (for example, in a row i and an intersecting columnj) if the temperature of that egg follows the trend.

The measured temperature (T_(Measured)(i,j)) for each egg is thencompared to the predicted temperature (T_(Predicted)(i,j)) for an egg atthat location (Block 719). Typically, the majority of the eggs (forexample, 70-90%) in a given flat will be live, in which case theT_(Predicted)(i,j) will be relatively close to the expected temperatureof a live egg. However, because the TTM may reflect the presence of somenon-live, non-clear eggs, the T_(Predicted)(i,j) for an egg at a givenlocation may be expected to be somewhat less than the expectedT_(Measured)(i,j) of a live egg at the same location in view of thetemperature trend analysis. Because a second-order fit may not followthe exact temperature distribution, errors may cause predicted livetemperatures to vary above and below live egg temperatures. Notably,because the temperatures of most of the non-live eggs (for example, theclear eggs and any other non-live eggs identified by light candling) areadjusted for use in generating the TTM, the tendency for the presence ofthe clear eggs or other non-live eggs identified by light candling inthe flat to skew the T_(Predicted)(i,j) away from the expectedT_(Measured)(i,j) of a live egg is minimized.

In view of the foregoing observations, the eggs may be evaluated asfollows:

1. If T_(Measured)(i,j)≧T_(Predicted)(i,j)−Y degrees, then the egg isclassified as live; and

2. If T_(Measured)(i,j)<T_(Predicted)(i,j)−Y degrees, then the egg isclassified as non-live

where Y is a constant select to account for the expected variancebetween T_(Measured)(i,j) and T_(Predicted)(i,j) due to the presence ofnon-live, non-clear eggs (i.e., the presence of non-live eggtemperatures in the ATDS). Y is also selected to reflect the desiredbias against discarding live eggs as weighed against the desired biasagainst retaining (and treating) dead or rotted eggs. Typically, Y willbe about 1° F.

The eggs earlier identified as clear eggs using the light candling dataare not classified using the TTM.

The foregoing method (Method B) using a TTM may be modified(hereinafter, the modified method is referred to as “Method C”). Ratherthan adding X degrees to the clear eggs in creating the ATDS, thetemperatures of the clear eggs may be excluded from the ATDS in the samemanner as the temperatures of the empty and upside-down eggs.

The foregoing Method B and Method C effectively eliminate the clear andother non-live egg temperatures from the classification determination,thereby providing the improvements in accuracy and other advantagesdiscussed above with regard to Method A. Additionally, by using the TTM(i.e., the predicted temperatures), the methods compensate or correctthe temperatures of the eggs for relative locations in the flat (i.e.,different micro-environments).

Temperature trends may be determined and Temperature Trend Maps may begenerated to correct or compensate the measured egg temperatures fordifferent micro-environments without using the light candling data, aswell. For example, each of the aforedescribed Methods A, B and C may bemodified such that the identification of clear eggs (or other non-liveeggs identifiable by light candling) is not required.

Method B may be modified (hereinafter, the modified method is referredto as “Method D”) such that the TTM is generated using the measuredtemperatures of all eggs (or, more preferably, all of the eggs exceptthose identified as upside-down). Restated, in Method D, Method B may bemodified such that the assigned T_(adj)(i,j) for all non-upside-downeggs will equal the T_(Measured)(i,j).

Similarly, the measured egg temperatures may be corrected or compensatedfor differences in micro-environments as described with regard to MethodA except that the temperature correction is performed using the measuredtemperatures of all of the eggs (or, more preferably, all of the eggsexcept those identified as upside-down) rather than only non-clears oronly the probable lives and rots (R) (hereinafter, the modified methodis referred to as “Method E”). The corrected egg temperature of each eggmay then be evaluated to determine if the egg is live or non-live usingone of the various methods described in U.S. Pat. No. 4,914,672 toHebrank or other suitable methods. For example, the individual correctedegg temperatures, rather than the measured temperatures, may be comparedto a threshold temperature to classify the eggs as live and non-live.

Each of the foregoing methods of correcting or compensating the eggtemperatures may be accomplished by evaluating the entire flat of eggsor, alternatively, by evaluating separate segments or portions of agiven flat independently. For example, a 7-egg by 24-egg flat may beevaluated as two 7 by 12 segments, with the selected method ofevaluating and classifying the eggs being performed on each segment asif it were a separate flat.

Using the foregoing methods, each of the eggs 2 in the flat isclassified as live or non-live. The non-live eggs may be furtherclassified as {clear or early dead} versus {mid-dead or late dead(depending on the day of candling) or rot} versus {missing} versus{empty} using the light candling data.

After the eggs are identified as live, clear, empty, missing, earlydead, mid-dead, late dead or rot, the results are displayed graphicallyon the display 42 (e.g., a screen of a PC computer monitor) along withcumulative statistics for a group or flock of eggs (Block 620). Suchcumulative statistics may be assembled, calculated and/or estimated bythe controller using the classification data. The cumulative statisticsmay include, for each group, flock or flat, fertility percentage, earlydead percentage, mid-dead percentage, upside-down percentage andpercentage of rots. These statistics may be useful to monitor andevaluate hatchery and incubator operation.

The flat is then placed on the conveyor 7B which transports the flat ofclassified eggs through the sorting station 60. Preferably, the eggsremain in a fixed array. The sorting station 60 physically removes theclear and early dead eggs from the flat 12 and directs them to acollector (Block 622). The clear and early dead eggs may be used forpurposes other than hatching broilers. For example, the clear and earlydead eggs may be used in the production of shampoo and dog food and aremore desirable when not contaminated with rot eggs. The sorting station60 may also remove the empty, rot, mid-dead and late dead eggs anddirect them to a separate collector.

The sorting station 60 may employ suction-type lifting devices asdisclosed in U.S. Pat. No. 4,681,063 or in U.S. Pat. No. 5,017,003 toKeromnes et al., the disclosures of which are hereby incorporated byreference herein in their entireties. Any other suitable means forremoving the eggs may be used as well, such apparatus being known tothose of ordinary skill in the art.

The sorting station preferably operates automatically and robotically.Alternatively, the selected eggs may be identified on the display 42,optionally marked, and removed by hand. The sorting station 60 may beprovided downstream of the treatment station 50, in which case thenon-live eggs will pass through the treatment station but will not beinoculated.

Following the sorting station 60, the flat 12 is placed on the conveyor7C which transports the flat 12 through the treatment station 50 (Block624). The flat will at this time hold all of the eggs which have notbeen removed, namely those eggs classified as live eggs. The eggs arepreferably maintained in their original, fixed array positions in theflat. The treatment station 50 may treat the remaining eggs in anydesired, suitable manner. It is particularly contemplated that thetreatment station 50 may inject the remaining, “live” eggs with atreatment substance.

As used herein, the term “treatment substance” refers to a substancethat is injected into an egg to achieve a desired result. Treatmentsubstances include but are not limited to vaccines, antibiotics,vitamins, virus, and immunomodulatory substances. Vaccines designed forin ovo use to combat outbreaks of avian diseases in the hatched birdsare commercially available. Typically the treatment substance isdispersed in a fluid medium, e.g., is a fluid or emulsion, or is a soliddissolved in a fluid, or a particulate dispersed or suspended in afluid.

As used herein, the term “needle” or “injection needle” refers to aninstrument designed to be inserted into an egg to deliver a treatmentsubstance into the interior of the egg. A number of suitable needledesigns will be apparent to those skilled in the art. The term“injection tool” as used herein refers to a device designed to bothpierce the shell of an avian egg and inject a treatment substancetherein. Injection tools may comprise a punch for making a hole in theegg shell, and an injection needle that is inserted through the holemade by the punch to inject a treatment substance in ovo. Variousdesigns of injection tools, punches, and injection needles will beapparent to those in the art.

As used herein, “in ovo injection” refers to the placing of a substancewithin an egg prior to hatch. The substance may be placed within anextraembryonic compartment of the egg (e.g., yolk sac, amnion,allantois) or within the embryo itself. The site into which injection isachieved will vary depending on the substance injected and the outcomedesired, as will be apparent to those skilled in the art.

FIG. 7 schematically illustrates a treatment station 50 that can be usedto carry out the selective injection methods of the present invention.The treatment station 50 comprises at least one reservoir 57 for holdingthe treatment substance to be injected into the eggs identified assuitable. A conveyor belt 53 forming a part of the conveyor 7C isconfigured to move the flat 12 of eggs 2. The direction of travel of theeggs along the conveyors is indicated by arrows in FIG. 7.

As the flat 12 of eggs is conveyed through the treatment station 50, thecontroller 40 selectively generates an injection signal to the treatmentstation 50 to inject those eggs which have been classified by thecontroller 40 as live eggs or eggs otherwise suitable for injection. Asused herein, the “selective generation of an injection signal” (or thegeneration of a selective injection signal), refers to the generation bythe controller of a signal that causes injection only of those eggsidentified by the classifier as suitable for injection. As will beapparent to those skilled in the art, generation of a selectiveinjection signal may be achieved by various approaches, includinggenerating a signal that causes the injection of suitable eggs, orgenerating a signal that prevents the injection of non-suitable eggs.

A preferred injector for use in the methods described herein is theINOVOJECT® automated injection device (Embrex, Inc., Research TrianglePark, N.C.). However, any in ovo injection device capable of beingoperably connected, as described herein, to the controller 40 issuitable for use in the present methods. Suitable injection devicespreferably are designed to operate in conjunction with commercial eggcarrier devices or flats, examples of which are described herein above.

Preferably, the injector comprises a plurality of injection needles, toincrease the speed of operation. The injector may comprise a pluralityof injection needles which operate simultaneously or sequentially toinject a plurality of eggs, or alternatively may comprise a singleinjection needle used to inject a plurality of eggs.

As shown in FIG. 8, the treatment station 50 may comprise an injectionhead 54 in which the injection needles (not shown) are situated. Theinjection head or the injection needles are capable of movement in orderto inject eggs. Each injection needle is in fluid connection with thereservoir 57 containing the treatment substance to be injected. A singlereservoir may supply all of the injection needles in the injection head,or multiple reservoirs may be utilized. An exemplary injection head isshown in FIG. 8, where the conveyor belt 53 has aligned the egg flat 12with the injection head 54. Each injection needle (not shown) is housedin a guiding tube 59 designed to rest against the exterior of an egg.Each injection needle is operably connected to a fluid pump 55. Eachfluid pump is in fluid connection with tubing 57A, which is in fluidconnection with the reservoir 57 containing the treatment substance.Suitable injection devices are described in U.S. Pat. No. 4,681,063 toHebrank, U.S. Pat. No. 4,903,635 to Hebrank, U.S. Pat. No. 5,136,979 toPaul and U.S. Pat. No. 5,176,101 to Paul.

Preferably, the eggs suitable for injection remain in the samecompartments in the same flat throughout the classifying, sorting andtreatment steps so that the eggs are prevented from changing theirpositions relative to other eggs while passing from the candling station8 to the injector. Preferably, each needle of the injection head 54 isaligned with one compartment of the egg flat (i.e., is aligned with theegg contained therein).

The selective delivery of treatment substance only to eggs identified assuitable can be accomplished by any of various means that will beapparent to those skilled in the art. Examples include, but are notlimited to, individually controlled fluid pumps, e.g., solenoid-operatedpumps; or individual valves that control the flow of treatment substancefrom a reservoir to an associated fluid pump. Alternatively, selectivedelivery of treatment substance may be accomplished by individualcontrol of injection needles or egg shell punches, so that punchesand/or needles do not enter those eggs identified as non-suitable. As afurther alternative, the eggs may be rearranged in the flat (forexample, all live eggs re-positioned to one end of the flat) tocorrespond to the locations of the needles or to otherwise simplify thevaccine dispensing system.

The treatment station 50 may be designed so that eggs can pass by in anuninterrupted flow. Where the eggs must come to a halt to be injected,it will be apparent to those skilled in the art that the use of anapparatus comprising more than one injection head may be desirable toincrease the speed of the overall operation.

The conveying system 7 may allow independent movement of conveyors 7A,7B, 7C so that an item placed on the conveyor 7A will pass to subsequentconveyors 7B and 7C automatically. The conveyor 7A may pass egg flatsunder the candling system 8 in a continuous flow, whereas the downstreamconveyor 7C may be used to move an egg flat to a position aligned withthe injection head 54 and halt while the eggs are injected. Movement ofthe conveyors 7A, 7B, and 7C may be under guidance of programmed orcomputerized control means or manually controlled by an operator. In apreferred embodiment, the conveyor belt 53 is supported by a frame 56which raises the conveying means to a height at which egg flats can beconveniently loaded.

Those skilled in the art will appreciate that many conveyor designs willbe suitable for use in the present invention. The conveyors 7A, 7B, 7Cmay be in the form of guide rails designed to receive and hold an eggflat, or a conveyor belt upon which an egg flat can be placed. Conveyorbelts or guide rails may include stops or guides that act to evenlyspace a plurality of egg flats along the conveying path.

The present invention is described in greater detail in the followingnon-limiting Examples.

EXAMPLE 1

Each egg of a ten row by five column (10×5) array of turkey eggs wasthermal candled and light candled. Each egg was thereafter broken openand inspected or otherwise evaluated to positively identify those eggswhich as actually live (L) or non-live (NL). Table 1 below lists themeasured temperatures of the eggs, along with their respective positions(i,j). FIG. 9 is a histogram graphically showing the distribution of themeasured, uncorrected egg temperatures.

The measured temperatures were used to identify the upside-down andempty eggs by calculating the average temperature of all of the eggs andclassifying those eggs having temperatures at least 5 degrees less thanthe average temperature as empty or upside-down. The egg temperatureswere corrected or compensated for location in the array using thecorrection method described above with regard to Method E, i.e., all ofthe eggs were used in the calculation except those eggs classified asempty or upside-down eggs. That is, the temperatures of clear, earlydead and mid-dead eggs, to the extent present, were used in thecorrection calculations. The temperatures corrected in this manner,without the benefit of light candling, are listed in Table 1 andgraphically displayed in FIG. 10.

The measured egg temperatures were also corrected or compensated by theMethod A described above, i.e., using the light candling data. The eggswere classified using the light candling data as either clear, earlydead or mid-dead (collectively, “C”) or, alternatively, dark (“D”). Themeasured temperatures were then corrected using only those eggs notclassified as empty, upside-down, clear, early dead or mid-dead in themanner described above. Table 1 lists the temperatures corrected usingthe light candling data. FIG. 11 graphically shows the distribution ofthese temperatures.

TABLE 1 Temp. Temp. cor- cor- Actual Light rected rected Conditionmeasure- without with (L = live; Meas- ment (C = light light EGG Col- NL= ured Clear; data data No. Row umn non-live) temp. D = Dark) (° F.) (°F.)  1 1 1 L 101.15 D 100.56 101.16  2 1 2 L 101.64 D 100.62 100.86  3 13 L 102.04 D 100.79 100.95  4 1 4 L 102.32 D 101.06 101.4  5 1 5 L100.44 D 99.37 100.17  6 2 1 L 101.22 D 101 101.33  7 2 2 L 101.46 D100.81 100.78  8 2 3 NL 99.36 C 98.49 98.37  9 2 4 L 102.64 D 101.75101.82 10 2 5 L 100.94 D 100.24 100.76 11 3 1 L 100.77 D 100.87 100.9912 3 2 L 101.25 D 100.92 100.68 13 3 3 L 101.24 D 100.69 100.36 14 3 4 L101.46 D 100.89 100.75 15 3 5 L 100.98 D 100.6 100.91 16 4 1 L 100.93 D101.3 101.27 17 4 2 NL 99.11 C 99.05 98.67 18 4 3 NL 99.08 C 98.8 98.3319 4 4 L 102.11 D 101.81 101.52 20 4 5 L 100.51 D 100.4 100.57 21 5 1 L100.55 D 101.13 101.03 22 5 2 NL 99.16 C 99.31 98.86 23 5 3 NL 99.03 C98.96 98.42 24 5 4 NL 99.66 C 99.57 99.21 25 5 5 L 100.69 D 100.79100.89 26 6 1 L 99.57 D 100.31 100.21 27 6 2 L 101.08 D 101.39 100.93 286 3 NL 98.92 C 99.01 98.46 29 6 4 L 101.3 D 101.37 101.01 30 6 5 L100.58 D 100.84 100.93 31 7 1 L 100.33 D 101.17 101.14 32 7 2 L 100.62 D101.03 100.64 33 7 3 L 100.95 D 101.14 100.66 34 7 4 L 101.77 D 101.94101.65 35 7 5 L 100.56 D 100.92 101.08 36 8 1 NL 97.52 C 98.41 98.51 378 2 L 100.26 D 100.72 100.46 38 8 3 L 101.11 D 101.35 101 39 8 4 L101.07 D 101.29 101.13 40 8 5 NL 97.84 C 98.25 98.55 41 9 1 L 100.15 D101.04 101.34 42 9 2 NL 98.38 C 98.84 98.78 43 9 3 L 100.71 D 100.95100.8 44 9 4 L 101.16 D 101.38 101.42 45 9 5 L 100.38 D 100.79 101.29 4610 1 L 99.73 D 100.56 101.13 47 10 2 L 99.98 D 100.38 100.6 48 10 3 L100.36 D 100.54 100.67 49 10 4 L 100.75 D 100.91 101.22 50 10 5 L 99.35D 99.7 100.47

Comparing FIGS. 9 and 10, it will be appreciated that correction orcompensation of the measured temperatures reduces the overlap betweenthe temperatures of the actual live and non-live eggs which are used todistinguish the live eggs from the non-live eggs. Comparing FIGS. 10 and11, it will be appreciated that correction of the measured temperaturesusing light data reduces the overlap between the temperatures of theactual live and non-live eggs which are used to distinguish the liveeggs from the non-live eggs as compared to correction without lightcandling.

Thus, the accuracy of the temperature correction and the advantages ofremoving clear and early-dead eggs from the calculation procedure isdemonstrated by temperature histograms of FIGS. 9, 10 and 11 thatcompare the results of no correction, correction based upon all eggsexcept empty and upside-down eggs, and correction without using clearsand early-deads in the calculation of the predicted and meantemperatures. As will be readily apparent, the correction proceduremakes live/dead classification more distinct and, more particularly,removing the clear eggs from the calculation significantly improvesclassification accuracy.

EXAMPLE 2

Using the information as set forth in Table 2 below, the eggs wereevaluated using Method D described above to generate a TTM including apredicted temperature (T_(Predicted)(i,j)) for each egg using thetemperatures of all of the eggs except those identified as upside-downeggs. These predicted temperatures are listed in Table 2. The predictedtemperatures were then compared to the corresponding measuredtemperatures to classify the eggs as live and non-live. The constant Ywas selected as 1.0° F. The resulting corresponding egg classificationsare also listed in Table 2. Comparing the actual conditions of the 50eggs to the determined classifications, it will be seen that only onelive egg was classified as non-live, and only one non-live egg wasclassified as a live egg.

Using the information as set forth in Table 2, the eggs were alsoevaluated using Method B as described above to generate a TTM includinga predicted temperature for each egg using all of the eggs except thoseidentified as upside-down. Additionally, the temperatures of the eggsidentified as clear were adjusted using a constant value of 2.0° F. forX. The predicted temperatures calculated for each egg are listed inTable 2. The predicted temperatures were then compared to thecorresponding measured temperatures to classify the eggs as live andnon-live. The constant Y was selected as 1.0° F. The resultingcorresponding egg classifications are also listed in Table 2. Comparingthe actual conditions of the 50 eggs to the determined classifications,it will be seen that no live eggs were classified as non-live, and nonon-live eggs were classified as live eggs.

TABLE 2 Actual Light Predicted Egg prediction Condition measurementtemp. for Y = 1° F. Predicted Egg prediction EGG (L = live; Measured (C= Clear; without (without temp. with for Y = 1° F. No. Row Column NL =non-live) temp. D = Dark) light data light) light data (with light)  1 11 L 101.15 D 101.07 L 100.89 L  2 1 2 L 101.64 D 101.50 L 101.68 L  3 13 L 102.04 D 101.73 L 101.99 L  4 1 4 L 102.32 D 101.74 L 101.82 L  5 15 L 100.44 D 101.55 NL 101.17 L  6 2 1 L 101.22 D 100.70 L 100.79 L  7 22 L 101.46 D 101.13 L 101.58 L  8 2 3 NL 99.36 C 101.35 NL 101.89 NL  92 4 L 102.64 D 101.37 L 101.72 L 10 2 5 L 100.94 D 101.18 L 101.08 L 113 1 L 100.77 D 100.38 L 100.68 L 12 3 2 L 101.25 D 100.81 L 101.47 L 133 3 L 101.24 D 101.03 L 101.78 L 14 3 4 L 101.46 D 101.05 L 101.61 L 153 5 L 100.98 D 100.86 L 100.97 L 16 4 1 L 100.93 D 100.11 L 100.56 L 174 2 NL 99.11 C 100.54 NL 101.34 NL 18 4 3 NL 99.08 C 100.76 NL 101.65 NL19 4 4 L 102.11 D 100.78 L 101.49 L 20 4 5 L 100.51 D 100.59 L 100.84 L21 5 1 L 100.55 D 99.90 L 100.42 L 22 5 2 NL 99.16 C 100.33 NL 101.20 NL23 5 3 NL 99.03 C 100.55 NL 101.51 NL 24 5 4 NL 99.66 C 100.57 L 101.35NL 25 5 5 L 100.69 D 100.38 L 100.70 L 26 6 1 L 99.57 D 99.74 L 100.26 L27 6 2 L 101.08 D 100.17 L 101.05 L 28 6 3 NL 98.92 C 100.39 NL 101.36NL 29 6 4 L 101.30 D 100.41 L 101.19 L 30 6 5 L 100.58 D 100.22 L 100.55L 31 7 1 L 100.33 D 99.64 L 100.09 L 32 7 2 L 100.62 D 100.07 L 100.88 L33 7 3 L 100.95 D 100.29 L 101.19 L 34 7 4 L 101.77 D 100.31 L 101.02 L35 7 5 L 100.56 D 100.12 L 100.38 L 36 8 1 NL 97.52 C 99.59 NL 99.91 NL37 8 2 L 100.26 D 100.02 L 100.70 L 38 8 3 L 101.11 D 100.24 L 101.01 L39 8 4 L 101.07 D 100.26 L 100.84 L 40 8 5 NL 97.84 C 100.07 NL 100.19NL 41 9 1 L 100.15 D 99.59 L 99.71 L 42 9 2 NL 98.38 C 100.02 NL 100.50NL 43 9 3 L 100.71 D 100.24 L 100.81 L 44 9 4 L 101.16 D 100.26 L 100.64L 45 9 5 L 100.38 D 100.07 L 99.99 L 46 10  1 L 99.73 D 99.65 L 99.50 L47 10  2 L 99.98 D 100.08 L 100.28 L 48 10  3 L 100.36 D 100.30 L 100.59L 49 10  4 L 100.75 D 100.32 L 100.43 L 50 10  5 L 99.35 D 100.13 L99.78 L

The use of both the light candling sensors and the thermal candlingsensors also facilitates the identification of faulty or dirty thermalor light sensors.

While certain preferred light and thermal candling systems have beendescribed herein, it will be appreciated that any suitable means forassessing the opacities and temperatures of the eggs may be used. It isintended that all such means shall be included in the present invention,means and methods using candling being merely preferred means andmethods for assessing the opacities and temperatures of the eggs inaccordance with the invention.

The foregoing is illustrative of the present invention and is not to beconstrued as limiting thereof. Although a few exemplary embodiments ofthis invention have been described, those skilled in the art willreadily appreciate that many modifications are possible in the exemplaryembodiments without materially departing from the novel teachings andadvantages of this invention. Accordingly, all such modifications areintended to be included within the scope of this invention as defined inthe claims. In the claims, means-plus-function clauses are intended tocover the structures described herein as performing the recited functionand not only structural equivalents but also equivalent structures.Therefore, it is to be understood that the foregoing is illustrative ofthe present invention and is not to be construed as limited to thespecific embodiments disclosed, and that modifications to the disclosedembodiments, as well as other embodiments, are intended to be includedwithin the scope of the appended claims. The invention is defined by thefollowing claims, with equivalents of the claims to be included therein.

That which is claimed is:
 1. A method for classifying poultry eggs, saidmethod comprising the steps of: measuring the opacities of the eggs;measuring the temperatures of the eggs; and classifying the eggs as afunction of both the opacities of the eggs and the temperatures of theeggs.
 2. The method of claim 1 wherein said step of classifying includesdistinguishing between clear eggs and at least one other class of eggs.3. The method of claim 1 including the step of injecting eggs of aprescribed class with a treatment substance.
 4. The method of claim 1including the step of reporting information relating to the eggclassifications.
 5. The method of claim 1 including the step ofseparating different classes of the eggs from one another.
 6. The methodof claim 1 wherein said step of classifying includes: classifying theeggs into first and second mutually exclusive groups using the opacitiesof the eggs; correcting the temperatures of the second group of eggs forrelative egg locations using the temperatures of the second group ofeggs and not the temperatures of the first group of eggs; andidentifying live eggs of the plurality of eggs using the correctedtemperatures of the second group of eggs.
 7. The method of claim 1wherein said step of classifying includes: classifying the eggs intofirst and second mutually exclusive groups using the opacities of theeggs; and classifying the second group of eggs using the temperatures ofthe second group of eggs and the identification of the first group ofeggs.
 8. The method of claim 7 further including correcting thetemperatures of the second group of eggs for relative egg locationsusing only the temperatures of eggs of the second group.
 9. The methodof claim 1 wherein said step of classifying includes: classifying theeggs into first and second mutually exclusive groups of the opacities ofthe eggs; and classifying the second group of eggs using thetemperatures of the second group of eggs and not the temperatures of thefirst group of eggs.
 10. The method of claim 9 further includingcorrecting the temperatures of the second group of eggs for relative egglocations using the temperatures of the second group of eggs and not thetemperatures of the first group of eggs.
 11. An apparatus forclassifying a plurality of poultry eggs each having an opacity and atemperature, said apparatus comprising: means for detecting theopacities of the eggs; means for detecting the temperatures of the eggs;and means for classifying the eggs using both the opacities of the eggsand the temperatures of the eggs.
 12. The apparatus of claim 11 whereinsaid means for classifying further distinguished between clear eggs andat least one other class of eggs.
 13. The apparatus of claim 11 whereinsaid treating means includes an injector operative to inject theprescribed class of the eggs with a treatment substance.
 14. Theapparatus of claim 11 including means for reporting information relatingto the egg classifications.
 15. The apparatus of claim 11 includingsorting means operative to separate different classes of the eggs fromone another.
 16. The apparatus of claim 11 wherein said means forclassifying: classifies the eggs into first and second mutuallyexclusive groups using the opacities of the eggs; corrects thetemperatures of the first group of eggs for relative egg locations usingthe temperatures of the first group of eggs and not the temperatures ofthe second grouped of eggs; and identifies live eggs of the plurality ofeggs using the corrected temperatures of the first group of eggs. 17.The apparatus of claim 11 wherein said means for classifying: classifiesthe eggs into first and second mutually exclusive using the opacities ofthe eggs; and further classifies the second group of eggs using thetemperatures of the eggs and the identification of the first group ofeggs.
 18. The apparatus of claim 17 wherein said means for classifyingcorrects the temperatures of the eggs for relative egg locations usingonly the temperatures of eggs of the second group.
 19. The apparatus ofclaim 11 wherein said means for classifying: classifies the eggs intofirst and second mutually exclusive groups using the opacities of theeggs; and further classifies the second group of eggs using thetemperatures of the second group of eggs and not the temperatures of thefirst group of eggs.
 20. The apparatus of claim 19 wherein said meansfor classifying corrects the temperatures of the second group of theeggs for relative egg locations using the temperatures of the secondgroup of eggs and not the temperatures of the first group of eggs.